Secondary battery and automobile

Abstract

The application relates to the technical field of energy storage devices, in particular to a secondary battery and an automobile. The secondary battery comprises a top cover plate, post terminals, anelectrode assembly and connecting members. Each connecting member includes a first connecting plate connected with a corresponding tab, a second connecting plate and a supporting plate. The supportingplates at least partially protrude towards the side close to a body part relative to the first connecting plates, and the protruding portions of the supporting plates fit the body part. In the heightdirection of the secondary battery, the minimum distance between each supporting plate and the bottom of the electrode assembly is the bare height H of the body part on its side. The dimension of thebody part along the length direction of the secondary battery is the length L of the body part, and the bare height H and the length L of the body part satisfy the following relational expression: 0.1<=H / L<=0.8. Black spots on a first or second pole piece can be avoided as much as possible, the energy density and cycle life of the secondary battery can be improved, and the safety of the secondarybattery can be improved.

Description

technical field [0001] The present application relates to the technical field of energy storage devices, in particular to a secondary battery and an automobile. Background technique [0002] Under the dual influence of energy and environmental pressure, electric vehicles have become more and more widely used, and secondary batteries, as their important power source, have an important impact on the performance and safety of the vehicle. Affected by the improvement of vehicle endurance requirements and policies, the requirements for energy density, cycle life, and safety of secondary batteries are getting higher and higher. The secondary battery includes an electrode assembly and a pole. The electrode assembly includes a main body and tabs extending from the main body. The main body is wound from a first pole piece, a separator and a second pole piece. In order to connect the pole and the pole The tabs are connected to transmit the current generated by the electrode assembly,...

AI Technical Summary

Problems solved by technology

Due to the increase of the size of the tabs and connecting members along the height direction of the secondary battery, the tabs and connecting members will hinder the internal exhaust of the electrode assembly, especially when the connecting member is attached to the main body, the electrode assembly will be closed at the main body. It is especially difficult to exhaust the blocked part

If the internal gas production rate of the electrode assembly is greater than the exhaust rate, bubbles will remain in the electrolyte, which will affect the transmission of lithium ions in the electrolyte, and may cause black spots on the pole pieces, thereby reducing the energy density of the secondary battery and making it reusable. life, and may pose a safety hazard

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